The present invention relates generally to film wrapping machines, and more particularly to a new and improved ring-type film wrapping machine for wrapping, for example, palletized loads within stretch film, and a method of operating the same, wherein the ring frame member, which normally carries or supports a wrapping film carriage and a roll of wrapping film mounted thereon, also has operatively associated therewith a mechanism for implementing the downward folding of outwardly projecting tab or peripheral edge portions of the plurality of slip sheets, which are interposed between the different tiers of goods or articles disposed upon the support pallet in order to separate and support the different tiers of articles or goods upon the support pallet, such that the wrapping film can be applied to the palletized load in a uniform and tightly wrapped manner, and wherein further, the outwardly projecting tab or peripheral edge portions of the plurality of slip sheets will not puncture and therefore adversely affect the structural integrity of the wrapping film or that of the integrated wrapped palletized load.
Ring-type film wrapping machines are well-known in the film wrapping industry for wrapping various articles, packages, loads, or the like, which are stacked and supported upon an underlying support pallet, within a suitable wrapping film. Examples of such ring-type film wrapping machines are disclosed, for example, within U.S. Pat. No. 6,195,961 which issued to Turfan on Mar. 6, 2001, U.S. Pat. No. 5,517,807 which issued to Morantz on May 21, 1996, and U.S. Pat. No. 4,587,796 which issued to Haloila on May 13, 1986. As can readily be appreciated, and as specifically disclosed, for example, within FIG. 1 of the present patent application drawings which corresponds to FIG. 1 of the aforenoted patent to Turfan, a conventional ring-type film wrapping machine 10 is seen to comprise a four-post upstanding framework 12 through which extends a conveyor 14 for transporting articles or palletized loads to be wrapped or packaged to a wrapping station 16 which is located substantially at the center of the region or boundary area peripherally defined by means of the upstanding posts of the framework 12. An upper horizontally disposed framework 18, which is vertically movable in a reciprocating manner with respect to the framework 12, rotatably supports a ring or circular track member 20 upon which is mounted a plastic film roll mounting and dispensing assembly 22 which includes a roll 24 of plastic wrapping film. Consequently, when the upper frame member 18 is moved in a vertically upward direction, after having been moved downwardly to a START position, and the ring or track member 20 is rotated with respect to the vertically movable upper frame member 18, film from the roll 24 of plastic wrapping film, mounted upon the film roll mounting and dispensing assembly 22, can be withdrawn or dispensed therefrom and applied to the articles or palletized loads which are disposed or located at the wrapping station 16 in preparation for being wrapped.
In order to form, for example, a stacked array of articles, packages, or loads upon the pallet, the articles, package, or loads are arranged within levels, layers, or tiers separated by means of suitable partitions or dividers known in the industry as slip sheets. The slip sheets present problems or difficulties, however, in connection with the actual wrapping of the articles, packages, or loads within the wrapping film. More particularly, since the peripheral edge portions of the slip sheets normally project externally beyond the peripheral vertical surfaces of the articles, packages, or loads disposed upon the pallet, such peripheral edge portions of the slip sheets do not readily permit the wrapping film to be applied to the palletized load in a uniform and tightly wrapped manner. In addition, the slip sheets are fabricated from a substantially rigid material and therefore the projecting peripheral edge portions of the slip sheets might cause penetration and puncture of the wrapping film thereby adversely affecting the structural integrity of the wrapping film as well as the integration or integral structure of the palletized load as formed in effect by the wrapped film.
A need therefore exists in the art for a new and improved mechanism, and a method of operating the same, for implementing the downward folding of the outwardly projecting tab or peripheral edge portions of the plurality of slip sheets, which are interposed between the different tiers of goods or articles disposed upon a support pallet in order to separate and support the different tiers of goods or articles upon the support pallet, such that the wrapping film can be applied to the palletized load in a tightly wrapped and uniform mode or manner, and wherein further the downwardly folded outwardly projecting tab or peripheral edge portions of the plurality of slip sheets will not adversely affect the structural integrity of the wrapping film or that of the integrated wrapped palletized load.
Accordingly, it is an object of the present invention to provide a new and improved mechanism, and a method of operating the same, for implementing the downward folding of the outwardly projecting tab or peripheral edge portions of the plurality of slip sheets which are interposed between the different tiers of goods or articles disposed upon a support pallet in order to separate and support the different tiers of goods or articles upon the support pallet.
Another object of the present invention is to provide a new and improved mechanism, and a method of operating the same, for implementing the downward folding of the outwardly projecting tab or peripheral edge portions of the plurality of slip sheets, which are interposed between the different tiers of goods or articles disposed upon a support pallet in order to separate and support the different tiers of goods or articles upon the support pallet, whereby such outwardly projecting tab or peripheral edge portions of the plurality of slip sheets will no longer present the operational disadvantages or drawbacks characteristic of PRIOR ART palletized load wrapping film systems.
An additional object of the present invention is to provide a new and improved mechanism, and a method of operating the same, for implementing the downward folding of the outwardly projecting tab or peripheral edge portions of the plurality of slip sheets, which are interposed between the different tiers of goods or articles disposed upon a support pallet in order to separate and support the different tiers of goods or articles upon the support pallet, whereby such outwardly projecting tab or peripheral edge portions of the plurality of slip sheets will no longer operatively interfere with the film wrapping operation being performed upon or in connection with the palletized load.
A further object of the present invention is to provide a new and improved mechanism, and a method of operating the same, for implementing the downward folding of the outwardly projecting tab or peripheral edge portions of the plurality of slip sheets, which are interposed between the different tiers of goods or articles disposed upon a support pallet in order to separate and support the different tiers of goods or articles upon the support pallet, whereby such outwardly projecting tab or peripheral edge portions of the plurality of slip sheets will no longer adversely affect the structural integrity of the wrapping film as well as the structural integrity of the integrated palletized load.
A last object of the present invention is to provide a new and improved mechanism, and a method of operating the same, for implementing the downward folding of the outwardly projecting tab or peripheral edge portions of the plurality of slip sheets, which are interposed between the different tiers of goods or articles disposed upon a support pallet in order to separate and support the different tiers of goods or articles upon the support pallet, whereby such outwardly projecting tab or peripheral edge portions of the plurality of slip sheets will no longer prevent the application of the wrapping film to and upon the palletized load in a uniform and tightly wound manner.
The foregoing and other objectives are achieved in accordance with the teachings and principles of the present invention through the provision of a new and improved mechanism, and a method for operating the same, for implementing the downward folding of the outwardly projecting tab or peripheral edge portions of the plurality of slip sheets, which are interposed between the different tiers of goods or articles disposed upon a support pallet in order to separate and support the different tiers of goods or articles upon the support pallet, wherein such mechanism comprises a second or auxiliary framework which, in a manner similar to that of the first or primary framework which rotatably supports the ring or circular track member and the plastic film roll mounting and dispensing assembly, is likewise vertically movable with respect to the four-post up-standing framework. The second or auxiliary framework comprises four independently movable framework members arranged in oppositely disposed pairs and wherein each one of the frame members has a pair of vertically oriented posts fixedly mounted thereon. The framework members are movable toward each other so as to locate the pairs of vertically oriented posts at positions immediately adjacent to the outermost edge or extremity portions of the plurality of slip sheets, and subsequently, the auxiliary framework will be lowered with respect to the four-post upstanding framework such that the vertically oriented posts cause the outwardly projecting edge or peripheral portions of the slip sheets to be folded downwardly against, adjacent, or parallel to the vertically oriented surfaces of the palletized load.
When the film wrapping operation is then commenced, the auxiliary framework is raised or elevated, along with the first or primary framework upon which the film roll mounting and dispensing assembly is disposed, such that as the palletized load is wrapped within the wrapping film from the lower end portion thereof to the upper end portion thereof, the downwardly folded edge portions of the slip sheets are accordingly temporarily secured in such a state by means of the vertical posts and are ultimately secured in such a state by means of the wrapping film. In view of the fact that the auxiliary framework posts are constantly being raised or elevated as the lower levels of the palletized load are being sequentially wrapped within the wrapping film, only a predetermined extent of the lower end portions of the posts are enveloped within the wrapping film at any one time. In addition, the lower end portions of the posts are coated with, for example, polytetrafluoroethylene (TEFLON(copyright)) so as to facilitate their subsequent withdrawal from the wrapped film as the first and second or primary and auxiliary frameworks are raised during the entire film wrapping operation or cycle.